Plant Parts and their Functions

1. Plant Parts and their Functions

2. Leaves-Internal

3. Leaves-Internal • Upper and lower epidermis-skin of the leaf that prevents the loss of too much moisture • Cuticle: waxy protective coating on outer surface • Stomas-small openings under the leaf for breathing or transpiration • Guard Cells-open and close stomas

4. Leaves-Internal Air Space: CO2 & O2 Vein: Movement of Fluid Xylem: transport water up Phloem: transport glucose

5. Leaves-Internal • Chloroplasts-small green particles that contain chlorophyll • gives leaves their green color • necessary for photosynthesis

6. Leaves-Internal

7. Functions of Leaves • Photosynthesis-manufactures food in green plants which is the beginning of the food chain for all living things • Photosynthesis is the process by which carbon dioxide and water in the presence of light are converted to sugar and oxygen

8. Functions of Leaves • Transpiration – loss of water through the leaves or stems of plants • Transpiration exchange gases as oxygen and carbon dioxide

9. Stems • Movement of Materials • Support of the leaves and reproductive structures • Food storages • Reproduction with stem cuttings or grafting

10. Stems-Internal (dicot)

11. Stems-Internal • Pith-dead center of stem for support • Heartwood-old inactive xylem • Sapwood-new active xylem • Cambium-thin, green, actively growing tissue located between bark and wood and produces all new stem cells • Phloem-active • Bark-old inactive phloem

12. Stems-Internal (Translocation) • Xylem-tissue that transports water and nutrients up from the roots to stems and leaves • Phloem-tissue that transports food down from leaves to roots Phloem Phloem Xylem

13. Stems-Internal • Monocot : examples: corn, grasses • Dicot: example: trees

14. Cotyledons -The primaryleaf of the embryo of a seed plant that either remains in the seed or emerges upon seedgermination

15. Functions of Stems • Translocation – move water and minerals from roots up to leaves & move food from leaves down to the roots • Xylem and phloem cells help with this process.

16. Functions of Stems & Leaves Transpiration – plant lose water from leaves and stems through evaporation Occurs in stomas and lenticels

17. Root Functions • Anchor the plant and hold it upright • Absorb water and minerals from the soil and conduct them to the stem • Store large quantities of plant food • Propagate or reproduce some plants

18. Roots-Internal • Much like stems in that they have a phloem, cambium, and xylem layer • Phloem-the outer layer that carries food down the root • Xylem-the inner layer that carries water and minerals up to the stem

19. Layers of Roots • Fibrous-many branched shallow roots • are easier to transplant • Tap-long root with few branched ones • more difficult to transplant

20. Functions of Roots • Absorption-take water and nutrients from the soil and conduct them to the stem • Anchor the plant and hold it upright • Store food for plant use • Asexual reproduction in some plants

21. Dioecious • Male and female, imperfect flowers on same plant • Examples: Squash & Pumpkin

22. Functions of Flowers • Produce seeds used for sexual reproduction • Attract insects for pollination (Pollination is the transfer of pollen from anther to stigma.) • Produce fruit to protect, nourish and carry seeds

23. Functions of Whole Plant • Respiration – the process through which plant leaves, stems and roots consume oxygen and give of carbon dioxide. • Plants produce much more oxygen through photosynthesis than they use through respiration.